I would go with Flygon, to get better type coverage, since you really don't have a proper counter for electric type pokemon, and both Vaporeon and Aerodactyl are weak to it. Also, Flygon is resistant to poison type and can be good against the Rocket Team grunts that use mainly poison type Pokemon.
Or you could go with Garchomp which has the same typing as Flygon (Ground/Dragon) and is faster and stronger than him, but I personally can't get past his stupid looking face that's why I use Flygon on my team. It's your choice.

I state that all the dragons are all most same. There is not much difference just they have little characters changing. You can have anything from flygon, kingdra,or dragonite. But i would personally suggest you to have Dragonite because i find it little unique. Also it can be extremely useful if used in the hands of a PokeMaster.

ur team isnt quite balanced as there are mainly physical sweepers
maybe you should get salamence like Raika said and only have special attacks as Salamence has pretty good special attack and speed
maybe drop aerodactyl and put on alakazam or gengar

ur team isnt quite balanced as there are mainly physical sweepers
maybe you should get salamence like Raika said and only have special attacks as Salamence has pretty good special attack and speed
maybe drop aerodactyl and put on alakazam or gengar